Abstract

New properties can arise at van der Waals interfaces hosting a moiré pattern generated by interlayer twist and strain. This work characterizes the spatial and temporal dependence of interfacial twist and strain relaxation in marginally twisted hBN/hBN interfaces heated under conditions relevant to vdW heterostructure assembly and sample annealing. The authors find minimal relaxation at 170°C in air, but significant twist relaxation at 400°C accompanied by reduced spatial uniformity; heterostrain initially increases and then decreases over time, with local inhomogeneity linked to structural irregularities such as step edges, contamination bubbles, or substrate contact.

Abstract

New properties can arise at van der Waals interfaces hosting a moiré pattern generated by interlayer twist and strain. This work characterizes the spatial and temporal dependence of interfacial twist and strain relaxation in marginally twisted hBN/hBN interfaces heated under conditions relevant to vdW heterostructure assembly and sample annealing. The authors find minimal relaxation at 170°C in air, but significant twist relaxation at 400°C accompanied by reduced spatial uniformity; heterostrain initially increases and then decreases over time, with local inhomogeneity linked to structural irregularities such as step edges, contamination bubbles, or substrate contact.

Abstract

New properties can arise at van der Waals interfaces hosting a moiré pattern generated by interlayer twist and strain. This work characterizes the spatial and temporal dependence of interfacial twist and strain relaxation in marginally twisted hBN/hBN interfaces heated under conditions relevant to vdW heterostructure assembly and sample annealing. The authors find minimal relaxation at 170°C in air, but significant twist relaxation at 400°C accompanied by reduced spatial uniformity; heterostrain initially increases and then decreases over time, with local inhomogeneity linked to structural irregularities such as step edges, contamination bubbles, or substrate contact.

Abstract

New properties can arise at van der Waals interfaces hosting a moiré pattern generated by interlayer twist and strain. This work characterizes the spatial and temporal dependence of interfacial twist and strain relaxation in marginally twisted hBN/hBN interfaces heated under conditions relevant to vdW heterostructure assembly and sample annealing. The authors find minimal relaxation at 170°C in air, but significant twist relaxation at 400°C accompanied by reduced spatial uniformity; heterostrain initially increases and then decreases over time, with local inhomogeneity linked to structural irregularities such as step edges, contamination bubbles, or substrate contact.